EulerHeisenberg
Euler-Heisenberg Lagrangian is a fundamental concept in quantum electrodynamics (QED), a theory that describes how light and matter interact. It was first derived by Leonhard Euler and Werner Heisenberg in the 1930s. The Euler-Heisenberg Lagrangian is a non-linear extension of the Maxwell Lagrangian, which describes the interaction of electromagnetic fields. It accounts for the vacuum polarization effect, where the quantum fluctuations of the electron-positron field induce a non-linear response of the electromagnetic field.
The Euler-Heisenberg Lagrangian is given by:
where L_M is the Maxwell Lagrangian and L_int is the interaction term. The interaction term is a
The Euler-Heisenberg Lagrangian has been experimentally confirmed through the observation of light-by-light scattering in high-energy particle